The present invention relates generally to the control of haptic feedback interface devices that interface a user with a computer device.
Humans interface with electronic and mechanical devices in a variety of applications, and the need for a more natural, easy-to-use, and informative interface is a constant concern. In the context of the present invention, humans interface with computer devices for a variety of applications. One such application is interacting with computer-generated environments such as games, simulations, and application programs. Computer input devices such as mice and trackballs are often used to control a cursor within a graphical environment and provide input in these applications. In portable computer or electronic devices, such as laptop computers or personal digital assistants (PDAs), mice typically have too large a workspace to be practical. A popular device for portable computers are “touchpads,” or touchscreens, which are small rectangular, planar pads that sense the location of a pointing object by any of a variety of sensing technologies.
In some interface devices, haptic feedback is also provided to the user. These types of interface devices can provide physical sensations which are felt by the user manipulating the user object of the interface device. One or more motors or other type of actuators are coupled to the device housing or manipulandum and are connected to the controlling computer system. The computer system controls forces output by the actuators in conjunction and coordination with displayed events. The computer system can thus convey physical force sensations to the user in conjunction with other supplied feedback as the user is grasping or contacting the interface device or manipulatable object.
In many haptic feedback devices, the haptic feedback takes the form of vibrations, jolts, or pulses output on the housing or manipulandum and are thus experienced by the user, referred to as “tactile” sensations herein. For example, many gamepad devices include a spinning eccentric mass that creates inertial vibrations on the housing or object. Other devices, such as the I-Feel Mouse from Logitech Corp., provide inertial vibrations using a linearly-moving mass. Still other devices may vibrate a housing or object by impacting or directly moving the housing or object with the actuator.
One problem with current haptic feedback devices is that tactile sensations output to the user tend to be more effective in particular frequency ranges and are less effective in other frequency ranges, thus causing haptic sensations to feel uneven and inconsistent to the user over broad frequency ranges.